EFFECT OF ADDITION OF DEXMEDETOMIDINE IN ROPIVACAINE AND BUPIVACAINE IN SENSORY AND MOTOR BLOCKADE AND POST OPERATIVE ANALGESIA IN AXILLARY BRACHIAL PLEXUS BLOCK FOR HAND AND FOREARM SURGERY

Abstract

Introduction: Axillary approach of brachial plexus block provides excellent operating conditions for forearm and hand surgeries with less risk. The α2:α1 selectivity of Dexmedetomidine is eight times that of clonidine and its high specificity for α2 subtype makes it a much more effective as adjuvant. The present study is designed to evaluate the effect of Dexmedetomidine as an adjuvant to 0.5% Ropivacaine hydrochloride with 0.5% Bupivacaine hydrochloride insensory and motor blockade and post operative analgesia axillary brachial plexus block in hand and forearm surgery.

Methodology: After institutional ethical committee clearance and informed written consent, prospective randomized controlled study of 60 patients of either sex, aged 18-60 years with ASA grade I, II and III undergoing forearm or hand surgery at SMIMER hospital was done.In Group 1, Inj. 0.5% Bupivacaine hydrochloride 20ml, Inj. 0.5% Ropivacaine hydrochloride 20ml and Inj. Dexmedetomidine (2µg/kg) were given. In Group 2, Inj. 0.5% Bupivacaine hydrochloride 20ml and Inj. 0.5% Ropivacaine hydrochloride 20ml was given. In operation theatre, Sensory blockade was assessed by three modalities. Pain (Pin Prick), Temperature (Alcohol wipe) and Touch (11 Point Scale). Motor Blockage by Lovett rating score, Sedation were assessed by Ramsay Score and Visual Analog Scale for Pain Relief were used.

Results: Demographic data like age, sex, weight of patients and surgical characteristics like duration & type of surgery were comparable in both the groups (P>0.05).The duration of motor blockade was significantly prolonged in Group 1 (p<0.01).VAS was comparable in immediate postoperative period upto 10 hrs but after that it became significantly higher in control group across the time. Mean total analgesic requirement (inj. Diclofenac sodium) was significantly less in 48 hours after performing axillary block in Group 1 (250 ± 35.95 mg) as compared to group 2 (405 ± 42.24 mg) (p<0.01).

Conclusion: Addition of dexmedetomidine to local anaesthetic agent in peripheral nerve block leads to decreased total consumption of analgesic postoperatively. Furthermore, in axillary brachial plexus block dexmedetomidine significantly prolonged both sensory as well as motor blockade and post operative pain relief.